1. Field of the Invention
The present invention relates to a stator for a dynamoelectric machine such as an automotive alternator, etc., and particularly relates to a stator construction for correcting circumferential mass imbalances caused by lead wires of a stator winding.
2. Description of the Related Art
A conventional stator for an automotive alternator is constituted by: an annular stator core in which slots extending in an axial direction are disposed at a predetermined pitch in a circumferential direction so as to open radially inward; and a stator winding installed in the stator core. The stator winding is constituted by three winding phase portions, the positions at which lead wires of each of the winding phase portions are led out from a rear-end coil end group being distributed within a circumferential range of approximately 120 degrees centered around a central axis of the stator core. Each of the lead wires is led axially outward from an apex portion of the rear-end coil end group and is connected to a rectifier apparatus. Thus, output from the stator winding is three-phase full wave rectified by the rectifier apparatus. (See Patent Literature 1, for example.)
Patent Literature 1: Japanese Patent Laid-Open No. HEI 9-19119 (Gazette: FIG. 1)
In the conventional stator for an automotive alternator, the lead wires of the stator winding are distributed in a state of imbalance relative to the circumferential direction, specifically within a range of approximately 120 degrees in a circumferential direction centered around the central axis of the stator core. The lead wires project axially outward from an axial end of the coil end group and vibrate easily.
Thus, when an automotive alternator mounted with the stator is mounted to an automotive vehicle, the lead wires vibrate when the stator is subjected to vibrations from the engine, etc., thereby subjecting the stator winding to vibration. As a result, one disadvantage has been that the vibration to which the stator is subjected is amplified by the stator winding, giving rise to wire breakages in the stator winding, particularly in the lead wires, thereby leading to defective power generation.
Another disadvantage has been that when the vibration of the stator is amplified, vibration of the alternator case supporting the stator also increases, making the reliability of the alternator poor.